Answer:
urban heat island
Explanation:
occurs when a city experiences much warmer temperatures than nearby rural areas.
Mark me brainliest.
Answer:
= 25 g
Explanation:
Using the formula;
A = A₀ (1/2)^(t/h)
where A is the final amount,
A₀ is the initial amount of the substance,
t is the time and
h is the half-life of the substance,
In this case; the half life of U-238 h is equal to 4.47 billion years.
A = A₀ (1/2)^(t/h)
A = 50 (1/2)^(4.5 / 4.47)
= 24.88
<u> = 25 g</u>
Number of moles = number of atoms/Avogadro's number
= (4.8x10^25)/(6.02x10^23)
=79.7 mol (3sf)
Because they cannot survive long outside a living host cell.
